So, I think this finishes off Tennyson for now.
The frames include the fact that Tennyson is in explicit control of the material: he tells the story, and keeps his distance. (A thing some of his earlier critics took him to task for.)
and there I shaped
The city’s ancient legend into this
The actions he described are completed, something “ancient”, existing in a past where miracles happened in a way they don’t in the present. Besides, he’s not telling us a factual story. “Ancient legend” explicitly undermines any truth claim the tale might have and once more invites us to see this on the level of a story about monsters or heroes. A story about Lady Bloggs, who rode naked round the streets of London in 1840, to help the poor of the city, would be unbelievable. Just as we're not invited to consider the long term consequences, we’re not invited to consider the reality of a real woman riding naked in a real city in the West Midlands of England.
Within the poem there are other frames to contain the action. Spatial: She rides to the gate, and returns. Temporal: She knows she must be back by Midday.
Above all, she steps out and uncovers herself, with her husband’s express permission, painfully aware of the shame she risks in her actions, and at the end of the ride she hurries back:
but even then she gain’d
Her bower; whence reissuing, robed and crown’d,
To meet her lord, she took the tax away,
And built herself an everlasting name
She removes the signs of her status as married woman but she rides out and back, she gets to the gate and turns, and turns within a set time limit. Her position hasn’t been changed, she has merely been allowed to do this thing. Any real power here is Leofric’s: he sets the terms of her actions, even though he does it negatively, and gives permission to her to transgress social and cultural norms of behaviour, for a limited time. She exposes to the world what is his; her body, she makes public what language describes as private. But she is trapped. She finishes off robed and crowned, the earl’s golden eagles presumably back round her waist. as she began, wearing the signs of her husband’s ownership; a feme coverte. Her act of individually has been sanctioned and contained: the commonplace of “her lord” casually reinforces her position in the feudal hierarchy of their marriage, and the fact that Tennyson tells us nothing about Leofric’s reaction suggests he is unchanged by it all. If Lady G is an icon, she is an icon of subservient action. Sanctioned rebellion is no real rebellion at all.